[Mlir-commits] [mlir] [mlir] Introduce OpAsmAttrInterface for pretty-print (PR #124721)

[Hongren Zheng]

================
@@ -1159,15 +1160,31 @@ template <typename T>
 void AliasInitializer::generateAlias(T symbol, InProgressAliasInfo &alias,
                                      bool canBeDeferred) {
   SmallString<32> nameBuffer;
-  for (const auto &interface : interfaces) {
-    OpAsmDialectInterface::AliasResult result =
-        interface.getAlias(symbol, aliasOS);
-    if (result == OpAsmDialectInterface::AliasResult::NoAlias)
-      continue;
-    nameBuffer = std::move(aliasBuffer);
-    assert(!nameBuffer.empty() && "expected valid alias name");
-    if (result == OpAsmDialectInterface::AliasResult::FinalAlias)
-      break;
+
+  OpAsmDialectInterface::AliasResult symbolInterfaceResult =
+      OpAsmDialectInterface::AliasResult::NoAlias;
+  if constexpr (std::is_base_of_v<Attribute, T>) {
+    if (auto symbolInterface = mlir::dyn_cast<OpAsmAttrInterface>(symbol)) {
----------------
ZenithalHourlyRate wrote:

The type variant of getAlias does exist but when we `mlir::dyn_cast<OpAsmAttrInterface>(Type)` MLIR will segfault so I guard it with `if constexpr (std::is_base_of_v<Attribute, T>)`.

When another PR introducing `getAlias` method for `OpAsmTypeInterface`, the code here would be

```cpp
if constexpr (std::is_base_of_v<Attribute, T>) {
  if (auto symbolInterface = mlir::dyn_cast<OpAsmAttrInterface>(symbol)) {
  ...
  }
} else if constexpr (std::is_base_of_v<Type, T>) {
  if (auto symbolInterface = mlir::dyn_cast<OpAsmTypeInterface>(symbol)) {
  ...
  }
}
```

https://github.com/llvm/llvm-project/pull/124721